Biomedical subjects

M H Cho

Publications and source records attributed to M H Cho.

5 recordsLinked to original sources

PubMed1991

A clinical study of patient acceptance and satisfaction of Varilux Plus and Varilux Infinity lenses.

An independent study was conducted at the UAB School of Optometry to determine the clinical success with Varilux Plus (Varilux 2) and Varilux Infinity progressive addition lenses (PAL). Two hundred eighty patients (280) were fit between June 1988 and May 1989. The acceptance rate of 97.5 percent was based on the number of lenses ordered versus the number of lenses returned. Patients were contacted by telephone and asked to rate their level of satisfaction with their PALs. A chi-square (non-parametric) test revealed no statistically significant differences in levels of satisfaction with respect to gender, PAL type, or degree of presbyopia. Also, neither refractive error nor previous lens history had a measurable impact on patient satisfaction.

Eyeglasses↗

PubMed1991

The effect of excessive add power on the acceptance of progressive addition lenses.

Twenty-nine subjects wearing Varilux Plus (Varilux 2) or Varilux Infinity lenses were drawn from the UAB School of Optometry primary care clinic population. Using a double-masked, randomized cross-over design, subjects wore one pair of progressive addition lenses (PALs) with a normal add and one pair with the add overplussed by 0.50 D. Subjects wore each pair of lenses for 1 week. Twenty-five of the 29 patients preferred the normal add over the overplussed add. In all subjective response categories the normal add was rated higher than the overplussed add.

Adult↗

PubMed1990

Clinical utility of partial flip angle T2-weighted spin-echo imaging of the brain.

To assess the clinical usefulness of partial flip angle (PFA) spin-echo (SE) brain imaging, a total of eighty patients were examined with both conventional double echo T2-weighted SE (2500/30, 80/90 degrees/one excitation) and PFA double echo SE (1200/30, 70/45 degrees/two excitations) on 2.0T system. Two comparative studies were performed: (1) in 65 patients PFA SE technique was compared with conventional SE without flow compensating gradients, and (2) in 15 patients the former was compared with the latter with flow compensating gradients. Imaging time was nearly identical in each sequence. In both studies we found that PFA T2-weighted SE images were almost identical to those obtained with the conventional SE technique in the contrast characteristics and the detection rate of the abnormalities (100%, 85/85 lesions), and more importantly, PFA SE revealed few flow artifacts in the brain stem, temporal lobes and basal ganglia which were frequently seen on conventional SE without flow compensating gradients. Additionally, PFA SE images demonstrated no suppression of CSF flow void in the aqueduct which was commonly seen on conventional SE with flow compensating gradients. In overall image quality, the PFA SE images, particularly the second echo images, were almost comparable with those of conventional SE with flow compensating gradients. A flip angle of 45 degrees seems to be close to Ernst angle, the angle at which maximum signal occurs, for a given TR of 1200 msec for CSF and most of the abnormalities containing higher water content.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

CSF flow artifact reduction using cardiac cycle ordered phase-encoding method.

The flow effects appear as a change of phase as well as signal intensity in NMR imaging. Since the flow of blood and CSF (cerebrospinal fluid) is pulsatile due to the heart pumping, their velocities are not constant during NMR imaging. This type of velocity fluctuation such as the blood or CSF flow induces irregular flow-dependent phase shifts, which have been one of the main causes of flow artifacts in NMR imaging. In order to reduce the flow artifacts, especially the CSF flow artifacts, a new cardiac cycle ordered phase encoding method is proposed and has been studied. This proposed technique utilizes the cardiac cycle as a precursor for the phase encoding gradients similar to the ROPE (respiratory ordered phase encoding) technique which has been used for respiratory motion artifact reduction. The basic concept and its applications are discussed together with the experimental results obtained with human volunteers using the KAIS 2.0 2.0 T whole-body NMR imaging system.

Brain↗

PubMed1989

A comparison of self-assessed satisfaction among wearers of dentures, hearing aids, and eyeglasses.

Patient assessment of dental prostheses, hearing aids, and eyeglasses can provide valuable data regarding adaptability of geriatric patients. This article describes a cross-modality evaluation of patient satisfaction with dental, hearing, and vision prostheses. Three hundred ninety-one subjects with recently placed prostheses were evaluated for self-assessed satisfaction and other related information. Patient satisfaction was compared with, age, type of prosthesis, and level of impairment. No statistical evidence of an age-related dissatisfaction with prostheses was found. Significant differences in levels of satisfaction were noted between different types of prostheses. Irrespective of level of impairment, patients expressed greatest satisfaction with dental prostheses and least satisfaction with hearing aids.

Aged↗